


Minato-san's Weakness

by Seigetsu_Ren



Series: YukiSayoChisa Stories [1]
Category: BanG Dream! Girl's Band Party! (Video Game)
Genre: Aged-Up Character(s), Background Poly, Cohabitation, Established Relationship, F/F, Multi, Sexual Humor
Language: English
Status: Completed
Published: 2019-11-23
Updated: 2019-11-23
Packaged: 2021-02-26 06:09:06
Rating: Mature
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 2,383
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/21528850
Author URL: https://archiveofourown.org/users/Seigetsu_Ren/pseuds/Seigetsu_Ren
Summary: If Sayo can't turn the tables on Chisato's autocracy, she can...sell her soul to the devil for a chance to top Yukina.
Relationships: Hikawa Sayo/Minato Yukina, Hikawa Sayo/Minato Yukina/Shirasagi Chisato
Series: YukiSayoChisa Stories [1]
Series URL: https://archiveofourown.org/series/1841098
Kudos: 72





	Minato-san's Weakness

**Author's Note:**

> Let it be known I posted the first YukiSayoChisa fic on ao3, muahahaha.
> 
> Ridiculousness to follow. You have been warned.

The process of how Chisato, Yukina, and Sayo herself had entered a relationship was a long story to tell. “Sayo-chan is such a masochist that one bully girlfriend isn’t enough; she needs two” was how Chisato would summarize the events if you were to ask her. Sayo did not like this explanation. She even had a rebuttal; it was Chisato who had a perverted interest in dominating the seemingly indominable, and one wasn’t enough.

At any rate, it was Chisato’s favourite secret pastime to top the hell out of her girlfriends. Maybe Aoba Moca’s lucid April Fool’s dream of Chisato being the evil incarnate wasn’t so unfounded after all, not that Chisato’s legion of devoted fans would ever decipher it from her sweet and cutesy public demeanour. Sayo had first-hand witness accounts of Chisato bringing Yukina the Lonewolf Songstress down to her knees (which was very hot to watch, by the way, if Sayo cared to admit). Of course, such indifferent observation would be short-lived as Sayo would fall prey next. Every single time. After Chisato was done with her, Yukina would take over to further crush Sayo’s ego, leaving her writhing and panting on the bed as though that’d make Yukina feel better about her previous (pleasurable) demise by Chisato.

While Sayo would very much like to take revenge on Chisato, she had conceded that even Yukina and her own iron wills combined would not make a dent in this ultimate devil. So instead, she plotted against her band leader. Well…and just the imagination of a sweaty, naked Yukina clinging desperately to her while begging for more was really, _really_ hot. Fine, Sayo would admit it!

Though Sayo plotted, she hadn’t gotten very far with her plan. If she had been less ethical, she might’ve thought to get Yukina drunk to lower the latter’s inhibition. Then again, whenever they drank, Sayo would be first to collapse on the table. She could instead attack Yukina in her sleep? Probably not a good idea, because Yukina valued her sleep a lot, so much so that if you disturb her, she’d claw you out like a cat.

“Go for the ears,” Chisato whispered to Sayo before she boarded her flight earlier this morning. Chisato had some kind of fan event going on in the States and wouldn’t be back in Japan until three days later. At first, Sayo didn’t know what Chisato was talking about, but now that she had had more time to think about it, she came to an understanding – had Chisato been referring to…Yukina’s weakness?

Sayo knew exactly why Chisato had told her this – she must find it amusing to have Sayo catch Yukina unawares and flip the table on their usual dynamics. As much as Sayo did not like being played as Chisato’s personal chess piece, the thought of avenging her “spoiled” honour was far too enticing.

And so, Sayo decided to attack tonight.

Dinner had been uneventful, if not a little quiet. While all three girlfriends weren’t much of talkers, Chisato would break the silence if it got too stifling. “It’s starting to feel a bit too much like the office, don’t you think?” – she’d interrupt. Common topics of conversation were music, pets, trivial geographic or historical knowledge, and if Chisato was so inclined, complaining about her job. Without her around, Sayo wasn’t sure how to start a conversation with Yukina. She remembered this wasn’t so hard back in their high school days. Sayo must’ve become reliant on Chisato to break the ice that constantly froze over Yukina’s face without the latter’s own notice.

“I am full. Thanks for the meal.” Yukina took her dishes to the kitchen to wash them, signalling Sayo’s missed opportunity. After dinner, Yukina settled on continuing work on her latest composition for Roselia. What could Sayo do but let her be? Even the rest of Roselia wouldn’t appreciate Sayo’s interruption right that moment. So instead, Sayo moved to the other room to play with Leon.

The dog had appeared a little depressed with Chisato gone. It had just been half a day! This was such obvious favouritism, despite that Sayo loved him just as much! Sayo kept rubbing the golden retriever’s back, but he just gave a dog-groan that matched the huge ass pout consuming half his face. At long last, Sayo sighed. “Let’s see if your other mommy has decided to use the in-flight WiFi. Maybe you can video chat with her.”

As Sayo tapped open the app on her mobile phone, the dog perked up in anticipation. Kids…err…dogs these days. So obsessed with technology.

Chisato seemed to be online, the perks of being a super idol sitting in first-class with unlimited WiFi, Sayo supposed. She had in fact sent a message.

_Chisato: How is Leon doing? Has he missed me?_

That was her first thought? Sayo could not help feeling a bit envious of the dog. With two girlfriends to care about, Chisato decided to ask about the dog first…in _their_ group chat!?

_Sayo: I think Leon would appreciate a video chat with you._

_Chisato: Oh? I’m flattered! What a good boy he is!_

_Chisato: I do think I have some time left before the plane starts descending and the WiFi cuts out. Let’s do a video chat then._

Shirasagi Chisato, super idol, would video chat her dog instead of her girlfriends. Sayo gritted her teeth. Chisato could’ve at least said _something_ about Yukina and Sayo herself, right?

Sayo angrily brought up the chat screen. Chisato was already smirking into the camera when it was connected. “I do miss you too, Sayo-chan,” she said by way of greeting as though reading Sayo’s mind. “How are you?”

“It has only been half a day. What could’ve changed?” Sayo answered, a bit too snappy for her own liking. She had planned to play it cool too!

“I did not anticipate much, but something must have happened to make you frown like so.”

If Sayo was an archer with arrows, Chisato was an archer with words. That was a direct hit to Sayo’s façade, and it hurt!

“I am not a pop idol. I see no use in adorning an unnecessary grin on my face.” Sayo said with a roll of eyes to emphasize her make-pretend dislike for Chisato’s music. She’d never let anybody know how she sang Chisato’s fuwa fuwa, shuwa shuwa songs in the shower.

Chisato ignored Sayo’s statement, instead making circles with her hand on the screen as Leon leapt excitedly at it. At long last, she said with an amused tone, “I thought you might need some help with Yukina-chan…”

“I do not need help!”

The rebuttal came a little too quickly that Sayo immediately regretted it. She could predict Chisato’s reaction.

“Okay, I won’t say anything then…”

“Wait!”

If only Sayo’s loudmouth hadn’t rejected Chisato’s offer, she wouldn’t have had to resort to begging. Alas, regret never solved any problems. Sayo now had no choice.

“Well…” Sayo fidgeted. “I…err…actually…need some help. Just a bit.”

“A _bit_?” Chisato emphasized the quantity with an exaggerated lilt. She was having a field day with this.

“Okay. A lot. I have said it now; are you happy?”

“You take me as a bully, Sayo-chan, thinking I would be happy for your embarrassment. I am not so crude…”

“Shirasagi-san!!!”

Chisato giggled. She knew not to push more buttons when Sayo reverted to calling her by surname. Not that that would stop her from laying out some terms for her services.

“I would help you, but you’ve got to promise me…”

“Acai bowls for a month!”

“And dress up as Hina-chan to sing _Wonderland Girl_?”

“Rurururun…Yes, I get it. I will do it! Can we call this a deal now? This is becoming an outright extortion!”

“Very well. Only for you, Sayo-chan.” Chisato stroked her chin thoughtfully. She then stroked some more. Then stopped and stared at Sayo with a blank gaze. “Actually, I thought I had been clear about Yukina-chan’s weakness?”

“You said ‘the ears’. What about the ears!? Please…that was not a specific statement!”

“Sayo-chan is always so particular…”

“It is perfectly reasonable to ask for an elaboration on such a vague suggestion!”

Chisato shrugged. “I thought it had been obvious that I meant you could say something into Yukina-chan’s ears. Like…rub the ear gently with your fingers and mutter into it in an alluring tone. Can you accomplish this, Sayo-chan? It is not exactly a Herculean task…”

Sayo took notes. Literally. After she put Chisato’s words to paper, she looked into the camera of her smartphone again. “And what should I say?”

“Something that expresses your love for her?”

“Specifics, Shirasagi-san!”

Chisato might’ve snorted in a mixture of amusement and exasperation. “Fine. Say this if you are courageous enough…”

Sayo glared. How dare Chisato question her stone-cold _conviction_ of bringing Yukina down to her knees begging to be fucked?

“I want to eat you out like a French fry,” Chisato said.

There was a moment of silence as Sayo’s determination deflated in front of Chisato’s eyes.

“You said…What!?”

“I want to eat you out like a French fry. If you have enough guts, you may also add: I want to pry apart your salty lips and dip my tongue into your steaming moist core…”

“ **What kind of French fry is that???** ”

Chisato pried the airpods away for a moment before returning them to her ears. “Here is a hint: lower the volume when you’re speaking into Yukina-chan’s ear. She would not appreciate it if you made her deaf.”

“ **Like I would do that!** ”

And Sayo cut the video chat short, much to the dismay of Leon, who had slumped down onto the ground once more. “Not my fault your other mommy can be so infuriating when she is in one of her sadistic moods. How did I stand working alone with her on our cultural festival project back in high school?”

_(You had not only done that, but decided years later that it would be a good idea to date her too, Sayo-san)_

After the video call, Sayo moved out to the living room where she could keep an eye on Yukina while playing _Neo Fantasy Online_ with Rinko and Ako. She didn’t do all too well on their quest while distracted; she kept pressing the wrong buttons on the turn-based battle choices, leading to her character dying more than once, only to be revived by an exasperated Rinko with her precious potions. The latter said she was heading to bed early, followed closely by Ako, both clearly unwilling to carry Sayo in the game any more that night. It was a little too late to practice guitar, so Sayo opened up the _Garupa_ game and flexed her skills in the public room.

That soon got too boring when _Sanctuary_ got picked ten times in a row. It was her favourite song on the game, the anthem of her love with Yukina owing to how Sayo herself had suggested its lyrics, but at this moment, she would rather hear Yukina’s yelps and moans than her pre-recorded singing. She finally put aside her game at midnight, having reached around 300 in rank with little effort, and turned her focus onto Yukina.

She placed her hands onto Yukina’s shoulders and kneaded. “Isn’t it about time we go to bed?”

Yukina relaxed to the massage. She closed her eyes and leaned back. “Just a bit longer. I am almost done writing this section.”

A bit longer probably meant another two hours at the very least. “This isn’t healthy for you, Yukina.”

Catching Sayo’s concerned tone, Yukina lowered her pen. Well, aside from concern, Yukina had also heard some desperation. Believe or not, Minato Yukina was not as cold-hearted as most people perceived, especially when it came down to the needs of her girlfriends.

She shifted her chair back from the table and rose to her feet, turning to face Sayo so that she could cup the latter’s chin in her fingers. “It seems that I have left you feeling lonely tonight. For that, I apologize.”

Yukina narrowed her gaze, casting a shadow on her golden irises. Her lips curled in a smirk as her finger traced Sayo’s jawline and down to her neck. When she reached the top button of Sayo’s shirt, her hand was quickly clasped by Sayo’s, stopping her motion.

Sayo was not being a bottom tonight!

She stepped forward, pulling Yukina close by her waist. The forceful act made Yukina’s smirk even wider in amusement. Not funny! Sayo quickly recalled her plan and brought her free hand to Yukina’s ear.

The moment her fingers touched the delicate flesh, Yukina’s expression changed.

“Wha…What are you doing, Sayo?”

Yukina’s voice was a little startled, and as Sayo rubbed Yukina’s ear between her thumb and index finger, her face visibly reddened. It was as Chisato had said – Yukina’s ears really were her weakness. Did that mean Chisato’s silly choice of words to whisper in Yukina’s ear was also legit!?

Sayo cleared her throat. She brought herself close to the side of Yukina’s head. Even as her breaths fell on Yukina’s ear, she could feel Yukina shiver in her embrace.

“Yukina…” Sayo pushed her voice to a low, _sexy_ rumble.

“ _Eep_!”

Yukina jumped a little. The reaction was so cute that it spurred Sayo on with more confidence.

“I want to eat you out like a French fry. I want to pry apart your salty lips and dip my tongue into your steaming moist core…”

Yukina’s knees buckled and she would’ve fallen if she hadn’t gripped fistfuls of Sayo’s shirt to steady her balance. Exactly the reaction Sayo wanted. She grinned in triumph, sweeping Yukina off her feet to carry her into the bedroom.

Little did she know that Yukina’s brain was going haywire that moment. She had really wanted to laugh at the nonsense Sayo had just spouted. Really! But curse the way Sayo’s voice vibrated against her sensitive ear – Sayo could be saying “I am an attack helicopter” and it would’ve elicited the same reaction from Yukina, damn it!

It was all part of Chisato’s plan to embarrass them both. She couldn’t wait to be back in Japan to witness it all first-hand!


End file.
